P1434: THE RELATIONSHIP BETWEEN MEDICATION ADHERENCE, BARRIERS TO MEDICATION ADHERENCE, AND QUALITY OF LIFE IN SICKLE CELL DISEASE
Authors: Kathryn King, Savannah Winkler, Robert Liem, Jane Holl, Sherif Badawy
Journal: HemaSphere (2023)

Topic: 26. Sickle cell disease Background: Sickle cell disease (SCD) requires lifelong treatment and management. While hydroxyurea, voxelotor and/or crizanlizumab reduce complications and improve health related quality of life (HRQOL), adherence remains suboptimal, especially among adolescents and young adults (AYA). Further, patient barriers to adherence are poorly understood. Aims: Assess the relationship of patient medication adherence to barriers and HRQOL domain scores and understand factors contributing to variation in medication adherence among AYA with SCD. Methods: Sixty-one patients (10-25 years old) with SCD (all genotypes), receiving hydroxyurea, voxelotor and/or crizanlizumab participated in this single-institution longitudinal study over 12-months. Participants completed the Adherence to Refills and Medications Scale 7 (ARMS-7), Brief Medication Questionnaire (BMQ), and Patient Reported Outcomes Measurement Information System (PROMIS) HRQOL measures every 3-4 months. Written informed consents and assents were obtained. Patient characteristics were analyzed using descriptive statistics, and Wilcoxon rank-sum test, Kruskal-Wallis test, chi-square, and spearman tests to assess the relationships. Results: Participants (52% Female; 93% Black; median age of 14 years [IQR 12-18]), at enrollment, had a median (IQR) fetal hemoglobin (HbF) of 12.1% (7.9-24.9) and mean corpuscular volume (MCV) of 93.5 fL (80-104.2). Self-report adherence rates (median 12 [IQR 10-14]) were correlated with HbF (r= -0.44, P<0.001) and MCV (r= -0.27, P=0.03). Participants reported medication recall barriers or forgetfulness (41%), negative beliefs about medication (23%), and difficulty with access to medications, such as paying for refills (32%). Most patients endorsed ≥1 barrier domain (n=40, 66%). Patients with lower medication adherence were significantly more likely to report forgetfulness (P<0.01), access barriers (P<0.01) and negative beliefs (P=0.04), compared to patients with higher adherence (Table 1). The total number of adherence barriers endorsed by participants significantly correlated with adherence level (r= 0.48, P<0.001), indicating higher medication adherence in patients with fewer barriers. Patients with lower adherence reported worse physical stress (P=0.01), psychological stress (P=<0.01), anxiety (P=<0.01), depression (P=<0.01) and self-efficacy managing symptoms (P=0.02). Older patients (≥ 18 years of age) and females reported higher psychological stress (P<0.01; P=0.03) and anxiety (P<0.01; P<0.01), respectively. Patients with ≥1 SCD-related hospitalizations in the year prior to study enrollment had significantly worse self-efficacy managing symptoms (P=0.01) and pain (P=0.02) compared to patients with no hospitalizations. Furthermore, participants with negative beliefs reported significantly worse anxiety (P=0.03) and depression (P=<0.01) a trend toward significantly more fatigue (P=0.06) and social isolation (P=0.08) than those without negative beliefs. Participants with reported medication access barriers trended toward significantly worse physical stress (P=0.06), anxiety (P=0.08) and pain (P=0.08), compared to those without access barriers. Summary/Conclusion: A significant number of AYA with SCD have at least one medication adherence barrier related to access, forgetfulness, or negative beliefs. Lower medication adherence, age, gender, and negative beliefs were significantly associated with impaired HRQOL. These findings suggest that mitigating barriers to medication access, helping to reduce forgetfulness, and overcoming negative beliefs could contribute to improved HRQOL.Keywords: Sickle cell disease, Patient reported outcomes, Pediatric, Quality of life